﻿<blockquote class="extDef">
NOTE&nbsp; Definition according to ISO 10303-46:<br>
The light source directional is a subtype of light source. This entity has a light source direction. With a conceptual origin at infinity, all the rays of the light are parallel to this direction. This kind of light source lights a surface based on the surface's orientation, but not position.</blockquote> 

<blockquote class="extDef">
NOTE&nbsp; Definition according to ISO/IEC 14772-1:1997:<br>
The directional light node defines a directional light source that illuminates along rays parallel to a given 3-dimensional vector. Directional light nodes do not attenuate with distance. Directional light nodes are specified in the local coordinate system and are affected by ancestor transformations.</blockquote> 

<blockquote class="note"> 
NOTE&nbsp; Corresponding ISO 10303 entity: light_source_directional. Please refer to ISO/IS 10303-46:1994, p. 32 for the final definition of the formal standard.
</blockquote> 

<blockquote class="note">
NOTE&nbsp; In addition to the attributes as defined in ISO 10303-46 the additional property from ISO/IEC 14772-1:1997 (VRML) <em>AmbientIntensity</em> and <em>Intensity</em> are inherited from the supertype.
</blockquote> 

<blockquote class="history">
HISTORY&nbsp; New entity in IFC2x, renamed and enhanced in IFC2x2.
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